Some of the company's multifunction printers incorrectly reproduce numbers in scanned documents

Xerox has issued the first software patch intended to fix a problem in some multi-function printers that causes characters to be incorrectly reproduced when scanned.

The problem first came to light in early August when a German computer scientist noticed errors in the reproduction of a building floor plan. Examining a PDF document of the scanned plan, he noticed some figures printed in a small, fine font on a document were incorrectly copied.

"We have confirmed that errors can occur under a set of limited conditions when scanning 'stress documents' to PDF -- which can include very small font sizes, stray pixels and be difficult to read.A Given this finding, however uncommon, we have developed this patch which eliminates that possibility," the company said in a statement.

Xerox said the problem only occurs with such "stress documents," which it defines as those that have "small fonts, are hard to read, contain stray pixels and/or have been scanned multiple times."

The problem doesn't occur when documents are printed, copied or sent via fax.

"Our engineering team has been working around the clock to deliver the patch. We have conducted extensive testing both in our labs and in the field to assure a quality result and an easy installation," Xerox said.

The first patch is for the Xerox ConnectKey family, WorkCentre 75xx, WorkCentre 57xx and ColorQube 93xx machines. A second patch will be available next week that covers the rest of the affected products.

"I want to thank all of our customers, agents and partners around the world for working with us and providing feedback throughout this process," Rick Dastin, president of the Xerox Office and Solutions Business Group, said in a statement.